How does a scientific theory “approximate” a more fundamental one despite having completely different math?

Question

For example, how does Newtonian gravity happen to work just the same as GR on low energy scales? Is it simply a simplified special case version of GR, or is there something deeper mathematically going on?

In: 12

Answer 1

To use your example, both Newtonian gravity and GR are describing the same physical phenomenon. The difference between them is about 400 years of additional work done by several generations of physicists. People like Hamilton (not Alexander) and Lagrange and Mach expanded on, revised, and criticized Newton’s theories. Einstein was the beneficiary of all this work which helped him develop GR.